The properties of a proton-conducting membrane, also called a proton exchange membrane or proton electrolyte membrane (PEM), significantly influence PEM-based fuel cell performance. Problems with currently available membranes (such as perfluorosulfonic polymers) include low thermal stability under acidic conditions and dramatic loss in proton conductivity above 100° C. To overcome these problems, complicated sub-systems become necessary, including those for thermal and water management. Hence, there is an urgent need for PEMs having improved stability and performance.